Japanese Patent Application Laid-open No. 2006-120767 describes a coil component including a core and a coil wound around the outer periphery of the coil, in which plural protruding portions, each of which is arranged between winding portions of the coil to determine the position of each winding portion, are formed integrally with the outer peripheral surface of the core.
This coil component is manufactured in the following manner.
First, the core is inserted into the coil in a state where the diameter of the coil is increased by twisting it in a radially expanding direction.
Then, twisting of the coil is released to make the diameter of the coil elastically return to the original diameter. At this time, each protruding portion of the core is arranged between individual winding portions of the coil. In this manner, the coil is wound around the outer periphery of the core.
In this way, changes in positions of each of the winding portions are limited in the axial direction of the coil by the plural protruding portions.